With the development of communication technologies, mobile communication networks are also more and more advanced. The mobile WiMAX (Worldwide Interoperability for Microwave Access, worldwide interoperability for microwave access network) based on the IEEE (Institute of Electrical and Electronic Engineers, Institute of Electrical and Electronic Engineers) 802.16 wireless access technology attracts wide attention because it can provide high-speed data transmission capabilities.
In a mobile WiMAX network, when an Mobile Station (MS) transmits a service flow with an external network, the uplink service flow sent by the MS is generally transmitted to a Serving Access Service Network Gateway (Serving ASN-GW) through a Base Station (BS), and then transmitted by the Serving ASN-GW to an Anchor ASN-GW, and finally transmitted to the external network through an Home Agent (HA); and the downlink service flow sent by the external network is routed to the MS through a bearer path reverse to the uplink service flow direction. As shown in FIG. 1, when the above method is implemented to transmit a service flow between two MSs (MS1 and MS2), if the MS1 and MS2 are managed by a same Serving ASN-GW, and the path for transmitting the service flow between the MS1 and the MS2 is indicated by the dotted line shown in FIG. 1. As seen from FIG. 1, the transmission path of the service flow from the Serving ASN-GW to the HA is overlapped, thus causing redundancy of the transmission path and an unnecessary transmission delay of the service flow and transmission load of the core network. Therefore, it is proposed that the service flow between the MS1 and the MS2 is transmitted by performing Local Routing (LR). Specifically, as shown by the solid line in FIG. 1, the Serving ASN-GW directly transmits the service flow from the MS1 to the MS2, or directly transmits the service flow from the MS2 to the MS1.
In general, the network side authorizes the service flow of the MS according to the Quality of Service (QoS) subscription information of the MS or the policy of the operator. However, the local routing involves two MSs, the existing network side may not satisfy the requirement for authorizing local routing.